REHABILITATION OF MODERATE TO SEVERE TBI: NEUROLOGICAL DISORDERS: INTRACRANIAL COMPLICATIONS: COMPLICATIONS WITH RISK OF INFECTIONS   

  1. Depressed Skull Fractures
    • If fragment is depressed more than the thickness of the skull below the inner table, fracture is usually deemed significant
    • Diagnosis is usually via tangential skull radiographs
    • Nomenclature:
      • Closed or simple, if there is no overlying scalp laceration
      • Open or complex if there is an overlying laceration
        • More frequent than simple
        • Usually elevated and debrided to reduce risk of infection, since use of antibiotics is controversial. Surgery usually results in cosmetic deformity, but is sometimes performed to prevent epilepsy despite hazards

  2. CSF Fistulas
    • Result from tears in the dura due to basilar fractures
      • Signs of basilar fractures and fistula include CSF leak and pneumocephalus, hemotympanum, Battle's sign, hearing impairment, peripheral facial nerve weakness, periorbital ecchymosis, fractures of the frontal sinus, and anosmia
      • Other complications of basilar fractures include loss of structural brain protection, which may contraindicate the use of nasogastric tubes
    • Can create an increased risk for meningitis, apart from CSF leak and pneumocephalus

  3. CSF Rhinorrhea
    • Symptoms: Usually a watery discharge with a salty taste, free of mucin, that:
      • May increase with manual work or leaning over, be unilateral or bilateral, and be associated with a dull constant headache from low intracranial pressure, and that can be diagnosed by:
        • Quantitative glucose determinations of >30 mg/100 ml in clear nasal fluid, collected, if necessary, by the patient lying prone for several hours
        • Beta-2 transferrin assay for CSF if nasal discharge is bloody
      • Must be distinguished from a history of nasal discharge in a brain-injured patient which is typically bilateral, associated with sneezing and tearing, and contains mucin

    • Diagnosis: Indicative of a fistulous tract from the intracranial compartment through the dura and skull base, that must be identified since CSF rhinorrhea implies a 10-fold increased risk for meningitis. The fistulous tract is typically located in the ethmoid/cribriform plate, posterior frontal sinus, roof of the orbit, and sphenoid sinus regions
      • Signs and symptoms of the site:
        • Anosmia suggests fractures in the ethmoid region
        • Preservation of smell suggests fractures other than in the ethmoid region
        • Persistent rhinorrhea is usually indicative of fractures of the posterior wall of the frontal sinus
        • Anesthesia of the supraorbital nerves, subconjunctival ecchymosis, air in the orbit, depression over the frontal sinus region, and apparent bone fractures are usually indicative of frontal sinus fracture
        • CSF fistulas are usually indicative of fractures in the posterior wall of the orbit or near the nasofrontal duct
        • Profuse rhinorrhea suggests a leak into the sphenoid sinus
      • Recommended sequence of diagnostic tests to localize a CSF leak is:
        • MRI in an attempt to visualize the leak (but the false-negative rate is higher than with CT cisternography), followed by
        • CT cisternography, which is particularly efficacious in patients with an active CSF leak, but less effective if the leak is not active at visualization, followed by
        • Digital subtraction cisternography, which can add information to that obtained in CT cisternography

      (Radioisotope cisternography, the traditional diagnostic procedure, can identify and lateralize a CSF leak, but is not as precise in pinpointing the exact location)

    • Treatment: To decrease the high risk for meningitis associated with CSF rhinorrhea:
      • Surgical repair of frontobasal dural tears must be performed.
        • Extracranial repair is associated with low morbidity and mortality, a high success rate, preservation of the sense of smell, and no additional trauma to the brain
        • Intracranial repair is advantageous if there are other large intracranial mass lesions which should also be treated even if symptoms are minimal
      • Lumbar drainage may be performed postoperatively, but is not recommended as the sole treatment
      • Antibiotic prophylaxis remains highly controversial and is not usually recommended.

  4. CSF Otorrhea - Results when fractures of the temporal bone (both longitudinal and transverse types) and dural tear are combined with tympanic membrane tear. Unlike CSF rhinorrhea, CSF otorrhea almost always resolves spontaneously in < 1 week.

  5. Pneumocephalus is either air or gas produced by an anaerobic infection within the cranial cavity
    • Symptoms: Include headache, motor paresis, meningeal signs, and psychosis with 1-3 months postinjury, commonly in patients with fistula and concurrent rhinorrhea
    • Diagnosis: Usually radiological, although a succession splash heard by auscultation is usually indicative of pneumocephalus
    • Treatment: Usually involves repair of the underlying dural tear and fistula

  6. Penetrating Injuries, such as gunshot wounds in which the bullet is retained inside the skull and there is tissue necrosis along the bullet's path, and/or retained bone fragments, bring an increased risk for infection up to 10-fold. Therefore, surgical debridement is recommended, as is antibiotic prophylaxis.

  7. Cranioplasty is associated with infection and is therefore sometimes delayed for 6 months - 1 year or more postinjury.

Based on information in Medical Rehabilitation of Traumatic Brain Injury, L.J. Horn and N.D. Zasler, eds. St. Louis, MO, Mosby, 1996, except for information where other papers are cited.